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79 Cancri

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79 Cancri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cancer
Right ascension 09h 10m 20.85841s[1]
Declination +21° 59′ 47.1000″[1]
Apparent magnitude (V) 6.04[2]
Characteristics
Evolutionary stage giant
Spectral type G5 III[3]
B−V color index 0.871[4]
Astrometry
Radial velocity (Rv)−3.24±0.13[1] km/s
Proper motion (μ) RA: +2.933[1] mas/yr
Dec.: +5.027[1] mas/yr
Parallax (π)8.1569 ± 0.0676 mas[1]
Distance400 ± 3 ly
(123 ± 1 pc)
Absolute magnitude (MV)0.78[2]
Details
Mass2.30[4] M
Radius9.41+0.38
−0.57
[1] R
Luminosity57.6±0.6[1] L
Surface gravity (log g)2.88[5] cgs
Temperature5,076±47[4] K
Metallicity [Fe/H]−0.10[5] dex
Age770[4] Myr
Other designations
79 Cnc, BD+22°2063, GC 12655, HD 78715, HIP 45033, HR 3640, SAO 80674, WDS 09103+2200[6]
Database references
SIMBADdata

79 Cancri is a star in the constellation Cancer, located 400 light years from the Sun.[1] It is just visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 6.04.[2] This object is gradually moving slower to the Earth with a heliocentric radial velocity of −3.2 km/s.[1]

This is an aging giant star with a stellar classification of G5 III,[3] which indicates that, at the age of 770[4] million years, it has exhausted the hydrogen at its core and evolved away from the main sequence. The star has 2.30[4] times the mass of the Sun and has expanded to 9.4[1] times the Sun's radius. It is radiating 58[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,076 K.[4]

References

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  1. ^ a b c d e f g h i j k l Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  3. ^ a b Cowley, A. P.; Bidelman, W. P. (February 1979), "MK spectral types for some F and G stars", Publications of the Astronomical Society of the Pacific, 91: 83–86, Bibcode:1979PASP...91...83C, doi:10.1086/130446.
  4. ^ a b c d e f g Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114.
  5. ^ a b Liu, Y. J.; et al. (April 2014), "The Lithium Abundances of a Large Sample of Red Giants", The Astrophysical Journal, 785 (2): 12, arXiv:1404.1687, Bibcode:2014ApJ...785...94L, doi:10.1088/0004-637X/785/2/94, S2CID 119226316, 94.
  6. ^ "78 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-11.